The remains of the roman Castle can be visited
Roman Milecastle 37

Roman Milecastle 37 is an example of ancient military architecture and an integral part of Hadrian's Wall. It is located in Northumberland, England.
History+
The first archaeological investigation of this milecastle took place in 1853, followed by further excavations in 1907 and 1933. These works yielded finds, including a reused corner of a Hadrianic dedication slab and two altars dedicated to the deities Cocidius and Jupiter. Later excavations between 1988 and 1989 revealed three construction phases of the north gate, which was initially built, then blocked, and finally partially demolished. The milecastle featured a short axis and a Type I gateway.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Ozymandias
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 55.0123, -2.3376